From to stdmatch.net, Web sites abound for the infected who want to date the infected. One in four women is infected with genital herpes, and nearly one in five men according to the Centers for Disease Control and Prevention.
And a study in this week's Journal of the American Medical Association finds that one in four women has human papillomavirus, which can cause genital warts and cervical cancer.(Interactive: Test your STD knowledge) Once John got over the initial shock of his diagnosis, one of the first things he did was go online.
(Watch how daunting dating can be for those with STDs )"I went on Craig's List and posted a note that said, 'I live in Charlotte, North Carolina, and I'm a decent professional man, and I've ended up with this.' Someone then contacted me and said, 'Have you heard of Charlotteh?
Even knowing when to tell a prospective boyfriend about herpes is tough.
"It's confusing, because you don't know when the right time is to tell somebody.
Should you be up front and get it over with or wait until the person develops feelings for you?
(CNN) -- When John got divorced after 12 years of marriage, he took a deep breath and launched into the dating scene."And wham, with my very first girlfriend, I caught herpes," he says.
"You feel betrayed and all of a sudden separated from the rest of the world.
I thought at the time that the girl who gave it to me and I were the only people in the world who had it."But John and his date are far from alone.
And the growing number of people in similar situations has created a new industry: Internet dating sites just for people with STDs.
"I would have been happy to have had just one person to unload everything I was feeling," he says.
"Instead I found more than 500.""Charlotteh" was started two years ago by Pam - who, like John, doesn't want her last name used.